Lecture 17 Objectives [Nov 27]prev next

ART MOMENT: .
 

"The Worcester Hunt mosaic, the largest floor mosaic brought to America, was excavated in the 1930s from a villa in Daphne, a suburb of the ancient Roman city of Antioch, now a part of Antakya, Turkey. [cite]"

At the end of today's class you should

HAVE READ:

• [711-723] 

KNOW:

• the concept of an interface
• how a class declares its intent to conform to an interface
• that you can't instantiate an interface
• that an interface is a a type, thus variables can be defined to be "a reference to an object of any class that supports the interface"

BE ABLE TO:

• Explain what can be in an abstract class that cannot be in an interface

DAILY QUESTION:

• This question asks you to consider the same NumberNode and NumberList that you saw on Exam 2. Here they are:
  
   

  /** Node class representing an integer. */ public class NumberNode {   int          value;    /* node value. */   NumberNode   next;     /* next one. */   public NumberNode (int i) {     value = i;     next = null;   } }

  /** List of numbers. */ public class NumberList {   NumberNode head;  /* first one. */   /** prepend a NumberNode with i to the front of the list. */   public void add (int i) { … } }

  Consider that you are shown the following method in the NumberList class:

  /** Method in NumberList. */ public void doSomething() {    NumberNode node = new NumberNode(3);    NumberNode other = new NumberNode(5);    head = node;    other.next = node;    head.next = new NumberNode(7);    node.next = other;    other.next = null; }

  What is the resulting list? Much of HW4 focused on your ability to perform such low-level manipulation of linked lists. You need to be able to understand the impact of these statements above.

  
  
  
  
  
   

Sample Exam question(s)